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Sept. 20, 1949. D. J. mossHAFeT DUMP GRATE MECHANISM Filed Oct. 12, 1946 o v 3 3 3%@ l S .J s mlm a v 3 .a @N2 Patented Sept. 20, 1949 o aflezen DUMPLGLRATE DonaldohA Mosshaft--fV Ardmore. Bareseisnee t Westinghouse-Electric fCQliloration, East Pittsburgh, Pa., a corporationf' Pennsylvania Applieationictber-*ll 1946?y Serial-No.-r7025965 3- Claims This: invention. relates to stoker: apparatus, more 'partioidarly to;` dump; grate, mechanism therefor, and. has z for objects to; provide improved mechanism...of. character.

Anotherobjectvof theinventionis to prov-ide improvedumeans fornsupporting and opi-:ratings Adump grateestructurawherehy cascading of fuel fromthe grate 'properto .the ash-.pitsdurtingdnmping. period-s, is preventedand -..clin-ken formations bridging the. dumpwgrate; arev positively broken 4and I dumped.

Yet another object. offtheinvention is; to prof Vide, improved linkage Inechanismr for movinge plurality of elementsc-makingnp .a alunniv grate mechanism.,

The: foregoing: and other.` objects are. effected bythe; inxzention as. willy be.y .apparent from, the following; description :claims taken: in c conanection .with the accompanying; drawings,` ,forme 'ingza part of this'applicatinn'irin which;

Fig. l isia: transverse sectional; viewythrough a. :Stoker structureY embodying. the principles zof the present invention, -ithef dumngrate mechanism shown at the left of thisl iig-nre heilig.y in: its raisedY or. fuelffreceiving position and; the dump grate mechanism shown .at-the right heing iin its loweredor dumping position;

Fig. 2 is a fragmentary view of the dump grate mechanism of Fig: l', but showing the same in intermedi-ate position; and,

Fig. 3 is a fragmentary plan View. of--the 4dump grate mechanism, in the position shown at the left of Fig; i.

Referring now to the drawings more infdetail,

the reference character i9; indicates, in'itsV eng tirety, grate structure disposedin a furnace; Il, whose fron-t wall l2 is provided with openings I3 throughwhich fuel is adapted to be fed to;` the fg-rate surface by suitable mechanism the spreader or sprinkler type, indicated at i4., .ag

The furnace may be provided with side walls I having headers I6 from which tubes I1 eX- tend upwardly to overhead headers (not shown) in the usual manner.

In the construction herein shown, the grate i structure l0 comprises central or apex bars i9, a plurality of intermediate bars 20, 2l and 22, and end or pusher bars 23, all of these bars being joined in end-to-end relation by pivot pins 24 and providing a fuel-supporting surface of the A the particul 2 they @Re adaptedrto slide, the plates-2 6 being` 51.1.9- eerteei estructural members 2l and 2 8, Carried. b y the usual-concreteside Wallsf2'9 of the plenum chamber The central, or apes;-v bars I9. areI secured to supports 32.by pins 33., .the Supports '32. being fixedly Secured on vsella-reel.fr wrterxe ef a rocker shaft all-earned by:reen-inc l Strueture `I leemateel 0n Structural members: fililfitlfl and 33 The first intermediate bars zgnare supported brflieks '405,1 whesezlewer are rive-'Gally cenlnetted-te breeketss 4 1 earned by the structurel members 3 6', andy liillee-MTy estelzldefqrem peinte in termediatethezendsof the links 40 to thefree ends-of weer efr-me iS'ef-fbellferarrles '44; meunted en Shafts 45fearried by bearinaetweture 461. The lower arms 41 of the bell cranks 44 are connected threnghilinlse 48;. with the-rearward ende ef the Seeland-.intermediate levarev 2l andthese linke 48 .are connected intermediate their ends with llinks 49,V whose. other ends are pivotal-lyconnected to rocker.*.ignelneersi5l),` supported on bearings.5 l and provided with upper rocking surfaces 5'2 Aon which rest tnefthlird intermediate bars- 22;

It willlbefapnarent tat., irl-Operation oscillatory movement of.: thermale reeker'ehaft 44 will movement of theeentral-erbars 49.-; and mele ytether;leale are pyotallv connected series s with: the'- intermediate. bars 20, 2| and @andthe endfbars 23, and undulatory movement will-beimpertedte.V the entirefuelsupporting surface, with the action -of the bars onzone side-of :thegra-te opposed to the action of the barethe.o lepesteeide. Inserm-uch as grate: Structurevillustrated forms no, part-.of h represent; inventiongfurtherdiscussion thereof S-lbelieved unneeessaryexeeet that it may be pointedput that, theznumber of intermediate harseZjl, .2li-@nd z2-may be increased or `'decreased :denend-Izlemnermthe width of the Stoker,-

'Ihe present invention is primarily concerned with the dump grate mechanism, indicated `in its entirety by the reference character 55, this mechanism including rst members or grate bars 5B and second members or plates 51, considered in the direction of ash feed thereover, pivotally connected in end-to-end relation at 58. The for- Ward ends of the lirst members 56 are pivoted to the stationary supporting plates 26, as at 59, and the second members 51 are supported through pivotal connections 6D intermediate their ends, by links 62 Whose lower ends G3 are pivoted, as at 64, to the free ends of crank arms 65, xedly secured to dump grate shafts 61.

In operation, and considering the structure 3 as illustrated at the left of Fig. 1, the shaft 61 is rotated in counterclockwise direction to move the mechanism from its ash-retaining position as shown, to dumping position. During this movement, the free ends of the crankshafts 65 move downwardly and inwardly with the first members 56 stationariiy supported by the curved upper surfaces of the crank arms 65. The second members 57 swing downwardly about their pivotal connections 58 with the first members 55.

When the dump grate mechanism has moved to the intermediate position shown in Fig. 2, abutments 68 at the lower ends of the links 62 engage upon projecting structures 89, provided on the structural members 28, with the result that further clockwise movement of the shaft 61 (Fig. 2) causes an upward movement ofthe pivotal connections 69 between the links 62 and the second dump grate members 5i, with the result that the pivotal connections 58 between the two dump grate mechanisms are likewise raised until the two members `5t and 51 assume the final position shown at the right in Fig. 1. At this time, the first members 5S are inclined upwardly in the direction of ash movement thereover and serve to prevent cascading of the fuel from the grate surface to the ash pit i9, while at the same time they positively break up any refuse formations tending to bridge or obstruct the dump grates.

It will be apparent that the present invention provides a novel arrangement of two dump grate elements pivotally connected together in endto-end relation, whereby positive dumping action is effected while at the same time undesirable loss of fuel from the grate surface is prevented.

While the invention has been shown in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof.

What is claimed is:

1. Furnace dump grate structure comprising first and second members, considered in the direction of ash feed thereover, pivotally connected together in end-to-end relation; a fixed pivotal support for the front end of said first member; a movable support for said second member intermediate its ends; a first abutment on said movable support; a second fixed abutment; and means for moving said movable support through a predetermined path such that during the first portion of its movement the abutments are out of contact and the rst member remains stationary and the second member is inclined downwardly in the direction of ash feed, and during the second portion of its movement the abutments are in contact, which moves the first member to a position inclined upwardly in the 4 direction of ash feed and the second member to a position of greater inclination.

2. Furnace dump grate structure comprising first and second members, considered in the direction of ash feed thereover, pivotally connected together in end-to-end relation; a fixed pivotal support for the front end of said first member; a crank arm and a link providing a movable support for said second member and said link having a bearing surface; a fixed abutment; and

-means for moving said movable support through Y a predetermined path such that during the first portion of movement the bearing surface is out of engagement with the fixed abutment, the first member remains stationary and the second member is inclined downwardly in the direction of ash feed, and during the second portion of movement the link bearing surface engages the fixed abutment, thereby changing the motion of the movable support so that the first member is inclined upwardly in the direction of ash feed and the second member is further inclined.

3. Furnace dump grate structure comprising first and second members, considered in the direction of ash feed thereover, pivotally connected together in end-to-end relation; a fixed pivotal support for the front end of said first member; a crank arm; a link pivotally connected at one end to the free end of said crank arm and at the other end to said second member, whereby said crank arm and link provide a movable sup-port for said second member; a projection on said link; a fixed abutment; and means for imparting limited oscillatory movement to the crank arm with the link projection free of the abutment during part of the movement and in Contact therewith during the remainder of the movement, said abutment being so disposed with respect to said link that during the part of the crank arm movement that the projection is free of the abutment the first member remains stationary in its normal position and during the remainder of the crank arm movement the engagement of the projection with the abutment moves said first member to a position upwardly inclined in the direction of ash feed.

DONALD J. MOSSHART.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,165,793 McClave Dec. 28, 1915 1,393,598 Alpern Oct. 11, 1921 1,567,130 Fleming et al Dec. 29, 1925 1,804,638 Mosshart May 12, 1931 2,373,448 Beers Apr. 10, 1945 

